This invention relates to the field of door locks and security devices to prevent entry into a building or apartment by unauthorized persons.
Door locks known to the prior art include lock mechanisms which hold the door latch itself from movement to the unlatching position, sliding bolt locks which are mounted on the door, usually in a horizontal position, and slide to a locking position wherein the projecting end of the bolt lock seats in a recess mounted in the door jamb or the wall adjacent to the edge of the door when closed; also chain locks mounted on the door having a latching end which is received in a latching recess mounted on the door jamb or the wall adjacent to the edge of the door when closed. There are also numerous variations of door locks of these various kinds which are known to the prior art.
Such locks known to the prior art have the disadvantage that they are no stronger than their connections are to the respective door and door jamb or wall, or than the door and jamb are themselves. A long enough pry bar can provide enough leverage to break the screws loose which hold the lock recess or lock seat to the door jamb or door wall. Also, there is a crack between the edge of the door to which the lock bolt or hook is mounted and the door jamb or wall on which the corresponding lock seat or lock recess is mounted whereby various tools and devices can be inserted or forced through such crack to break or open the lock.
The door lock in accordance with the present invention overcomes such problems and disadvantages of the door locks known to the prior art. The anchor plate or anchor means is bolted or otherwise secured to the floor, or formed in the floor, to provide an anchor for one end of the locking bar which is more secure and more difficult to break loose than the door itself or the door jamb or edge of the wall adjacent the door opening. The locking bar of this invention is positioned longitudinally, or in line, with the direction in which the door opens rather than laterally as in prior art door locks. A locking bar placed longitudinally or in-line with the direction of opening, rather than laterally across such direction, is much more difficult to force open or break, if not impossible, from the opposite side of the door. The end of the locking bar which abuts against the bottom edge of the door near its unhinged side provides the most positive and most secure locking engagement possible, with no mounting screws to force out, and virtually no way to break or bend a locking bar in such position.